Beyond a general purpose, a speech should also have a specific purpose. For example, an informative speech may have the specific purpose of increasing listeners’ knowledge of the causes of global warming. The specific purpose of a speech will typically be evident by the time the speaker finishes the introduction, and must be unmistakably clear by the time the speaker begins the conclusion.
A speech that lacks a clear sense of purpose will seem to drift and wander as though it were a boat without a rudder, blown this way and that by whatever thought occurs to the speaker. Developing a clear purpose begins with the speaker considering audience needs. Speakers must determine precisely what they want to accomplish: what they want listeners to learn, think, or do as a result of their speeches.